Driving device for vehicle-speedometers.



P. M. MURRAY.

DRIVING DEVICE FOR VEHICLE SPEEDOMBTBRS.

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' "iran STATES PATENT FFIQE FRANK M. MURRAY, or 'cAnYvIL'L'E, New YORK.

DRIVING DEVICE FOR VEHICLE-SPEEDOMETERS.

'specificat'ion of Letters Patent.

Patented Oct. '7, 1913.

Application filed January 4, 1913. Serial No. 740,203.

determining the speed thereof and recording the distance traveled.

The primary object of the invention is to provide a device of this character embodying a disk fixed to one of the vehicle hubs, and 'a power transmission disk engaging the face of the disk on the hub, to transmit power through a flexible shaft to the mechanism of the speedometer, saidlatter disk being mounted upon the axle casing for movement relative to the disk on the hub.

Still another object of the invention re sides in the provision of improved. means for mounting the power transmitting disk,

whereby the same is at all times held in frictional contact with the face of the disk on the wheel hub but hasfree bodily movement when the wheel is moved with relation to its axle in steering the vehicle.

A still further-object of the invention is to provide a device of the above character wherein liability of the power transmitting means becoming clogged and failing to properly operate is eliminated, my improvements also resulting in considerable economy in the manufacture of such devices and greatly increasing the durability and operating efficiency thereof.

WVith the above and other objects in view as will become apparent as the description proceeds, the invention consists in certain constructions, combinations and arrangements of the parts that I shall hereinafter fully describe and claim.

For a full understanding of the invention, reference is to be had to the following description and accompanying drawings, in which Figure 1 is a side elevation of a portion of a motor vehicle showing my improvement applied thereto. Fig. 2 is a fragmentary view of the inner face of the wheel showing the manner of mounting the disk carrying arm, the casing therefor being in section; and Fig. 3 is a section taken on the line 3 -3 of Fig. 2.

Referring in detail to the drawings, 5 designates a speedometer of any ordinary or approved construction which is mounted in any preferred manner upon the dash board of the vehicle as shown in Fig. 1. The mechanism of the speedometer is driven through the medium' of a flexible shaft 6,

.upon the lower end of which the disk 7 is secured. This disk is provided upon its peripheral face with a band of rubber or leather indicated at 8 7 Upon the inner end of the wheel hub, a driving disk 9 is secured. This dish may be of any preferred construction and the inner face thereof is engaged by the friction band 8 on the disk 7.

The lower end of the flexible shaft 6 is mounted and supported in the upper end of an arm 10, the lower end of which is loosely mounted upon a rod or shaft 11, said shaft being fixed in any suitable manner in the opposite ends of the casing 12. This casing is integrally formed upon the lower end of a bracket arm 13 which is bolted or otherwise secured at its upper end to the axle casing 14. The casing 12 is provided in its top with an arcuate slot 15 in which the arm 10 is adapted to move. The power transmitting disk 7 on the upper end of this arm is yieldingly held in proper operative relation to the disk 9 on the wheel hub by means of a coil spring 16 which surrounds the shaft 11. One end of this spring is secured to the arm 10 while the other end thereof is fixed to one of the end walls of the casing 12. It is obvious from this construction that the spring 16 will at all times yieldingly hold the friction surface of the disk 7 against the face of the disk 9. hen, however, the vehicle wheel is turned in steering the machine, the arm 10 will be swung upon the shaft 11 against the action of the spring 16, and thus permit the power transmitting disk to move with the vehicle wheel. From the foregoing, the construction and manner of operation of my improved driving device will be clearly understood. By eliminating the use of cog gears, as is ordinarily employed in devices of this character, liability of stripping the teeth from the gears or of the same becoming clogged with mud or dirt, is avoided. The spring 16 assures a close frictional engagement between the peripheral frictional band on the disk 7 Copies of this patent may be obtained for and the face of the disk 9, so that power is transmitted to the mechanism of the speedometer and the proper operation of the same irrespective of the steering movements of the vehicle Wheel is obtained.

It will be apparent that in putting the invention into practice, I am not limited to the specific construction and arrangement of the several parts and the relative diameters of the disks may also be varied as may be required in view of the particular construction of the speedometer mechanism. It Will therefore be understood that I reserve the right to make such various modifications as may seem advisable and which will fairly fall Within the spirit of the invention and the scope of the appended claims.

By eliminating the usual cogs or'gears in devices of this character, the operation thereof is rendered practically noiseless.

Having thus described the invention, What is claimed is:

1. A driving device for vehicle speedometers comprising in combination With a flexible transmission shaft, a friction disk secured on one end of said shaft, a disk mounted upon the hub of the vehicle Wheel With which the friction disk on the shaft engages, a casing mounted upon the axle casing of the vehicle Wheel, an arm pivotaily mounted in said casing, in Which said transmission shaft is supported, and means Within the casing and connected to said arm to hold the friction disk in engagement with the disk upon the Wheel hub.

2. A driving device for vehicle speedometers comprising in combination with a flexible transmission shaft, a friction disk secured on the end of said shaft, a disk mounting mounted upon the axle casing of the vehicle, a shaft extending through said casing and fixed therein, an arm loosely mounted signature in the presence of tWo Witnesses.

FRANK M. MURRAY. Witnessesz I J J. BROMLEY, E. R. Powiins.

five cents each, by addressing the Commissioner of Patents, 1 7 Washington, D13. V

40 ed upon the hub of the vehicle Wheel, a cas- 

